This invention relates to product cushioning devices for use in packaging shock sensitive products. In particular, the invention relates to re-usable or recyclable product cushioning devices which are made from plastics material, and which are particularly intended for use with shock sensitive products such as computer componentsxe2x80x94particularly hard drives, CD and DVD drives, and the like. The configuration of cushioning devices in keeping with the present invention is typically as an end cap. Product cushioning structures in keeping with the present invention comprise unitary structures which may be molded from a suitable plastic material, using a thermoforming molding techniques.
The use of product cushioning devices for shock sensitive products has been known for many years. Typically, cushioning for shock sensitive devices comprises a number of different approaches, each of which may have its own particular advantages and/or disadvantages.
For example, it has been known for many years to wrap shock sensitive or delicate devices or merchandise in tissue paper, and to cushion the products with loosely balled tissue paper. Another use of paper has been shredded paper, or excelsior. A more elegant approach has been to use bubble-pack, which comprises a sheet material having a plurality of contained bubbles of air formed therein. Another approach which has been used for many years has been the use of a plurality of discrete molded foamed polystyrene pellets, sometimes referred to as xe2x80x9cpeanutsxe2x80x9d in the industry, to fill around a product in a container.
As the requirement for better packaging and cushioning became more demanding, for example with the introduction to the market of complicated and expensive electronics devices such as computer monitors, and more particularly notebook computers, printed circuit boards, and the like, the requirement arose for more sophisticated and better shock absorbing cushioning devices. Standards were developed for acceptance of cushioning devices, including drop tests and the like, to determine if such devices would protect the shock sensitive product from shock acceleration greater than the product""s fragility levelxe2x80x94typically, from 20 g""s to 100 g""s.
This has given rise to the use of such products as honeycomb cardboard, and particularly foamed polystyrene, foamed polyurethane, foamed polypropylene, or foamed polyethylene. Flexible foam devices are well known for use as corner pieces or edge pieces. Likewise, foamed polystyrene productsxe2x80x94which are more rigidxe2x80x94are also well known for use as corner pieces or end caps; and very often, they are product specific in that they are particularly molded having a specific configuration for use with a particular product.
In general, however, flexible foam cushioning devices, and foamed polystyrene cushioning devices, are not recyclable. There are several reasons for that condition: The first is that flexible foam cushioning devices, and polystyrene cushioning devices, tend to be quite bulky, and are usually discarded with the packaging container in which the product has been shipped. There are very few specific recycling depots that are set up for either flexible foam or especially polystyrene cushioning devices; and, in any event, foamed polystyrene and foamed polyurethane cannot generally be recycled. Its re-usability may be provided for, particularly as general corner pieces, if they remain intact, or as product specific end caps; but, unless such foamed polystyrene cushioning devices are being used in a closed shipping system, they will not be recovered for re-use. Moreover, foamed polystyrene cushioning devices tend to be very frangible, and do not maintain their integrity very well once they have been used and removed from the packaging container in which they are shipped.
More elegant cushioning devices have more recently entered the market, comprising different types of blow-molded or other plastics shell products, most of which are closed structures which are filled with air or other gas. Some such structures are inflatable, some are closed, and some may be open to the atmosphere but are formed of a relatively rigid material. All such products are generally formed from high density polyethylene, which may be recycled because it is easily chopped up and made into further products, or such products may be re-usable if they are employed in a closed delivery and recovery system. Low density polyethylene may also be found in products such as those described immediately above, although its use is quite limited at the present time.
Very often, computer components such as hard drives or CD or DVD drives, or resellers of the same, wish to package such shock sensitive devices individually in outer packaging containers. That is to say, these shock sensitive devices are packaged and shipped, or stored, in individual outer boxes. At the same time, however, it is not desired to employ excessive packaging materials such as those that are spoken of above. Accordingly, the present invention provides an end cap which may be placed at both ends of such shock sensitive devices, where the dimensions of the end cap, particularly in the base portion thereof, are such that the end cap fits intimately into an individual outer box; and the end cap has a product receiving recess or cavity such that the shock sensitive device may be received intimately into that cavity.
Thus, it can be appreciated that by employing a pair of end caps in keeping with the present invention, shock protection for individually packaged shock sensitive devices such as computer hard drives, CD or DVD drives, or the like, may be provided.
U.S. Pat. No. 2,874,826 issued to MATTHEWS et al. is directed to a shock and vibration isolation device which, however, is not intended for being incorporated in a rectilinear container. Rather, this device is a resilient and inflatable jacket comprising a plurality of chambers, made of a rubberized fabric which is adapted to hold a gas under pressure, and which will be wrapped around a shock sensitive device such as a guided missile so as to provide a shock and vibration isolation container therefor.
GOBAN U.S. Pat. No. 3,294,223 teaches a molded plastic corner piece having the configuration of a triangular polyhedron which is either rounded or flattened at its apex. The purpose of the corner support is to entrap air between the molded plastic corner piece and the corner of the carton into which it is placed.
U.S. Pat. No. 4,905,835 issued to PIVERT et al. teaches inflatable cushion packaging wherein a plurality of chambers are inflated so as to provide cushioning which will absorb shock and thereby protect a shock sensitive product located in the centre of the container. The amount to which the balloon-like chambers may be inflated, and therefore their hardness, may be controlled.
FOOS et al. U.S. Pat. No. 5,226,543 teaches a packaging structure which includes both a platform portion and a sidewall portion, wherein the sidewall portion forms an enclosure around the platform portion. Essentially, this product is an end cap or platform. The sidewall has both inner and outer walls which are joined by a bridge section, and the inboard wall is relatively shorter than the outboard wall such that the platform portion holds the fragile article at a specific distance above the lower edge of the outboard wall. Shock absorbing formationsxe2x80x94typically, notchesxe2x80x94are formed in the bridge portion of the sidewall. These notches have a degree of elasticity such that, when the packaging structure is loaded and then unloaded, or shocked and then unloaded, the notch will return to its original shape and can absorb multiple loads without deteriorating. However, in order for the elasticity to exist, a material with a high degree of stiffness must be usedxe2x80x94typically, that material is high density polyethylene. The patent requires that the inboard wall is shorter than the outboard wall.
Another patent issued to Foos et al. is U.S. Pat. No. 5,385,232. This patent also teaches a sidewall structure which forms an enclosure around a platform portion. However, the teachings of this patent also address the issue of light shock loads that may not deform or compress the shock load formationsxe2x80x94the notches that are discussed in the previous Foos et al. patent. Here, the concept of openings which provide for collapsibility and allow for the release of compressed air beneath the package when the package is subject to shock loading, is introduced. These collapsible openings may be located in the platform at various locations, and may have a variety of shapes. Still, like the other Foos et al. patent, the teaching is directed to the use of inboard and outboard walls as well as the use of the shock formations (the notches) that have an elastic characteristic.
MOREN et al. U.S. Pat. No. 5,515,976 teaches a structure which has side flanges that are adapted to contact all sides of an end portion of a fragile article, and is thus configured as an end cap. There are a number of protrusions disposed throughout the sidewalls to support the article. There is also a notch provided in the side wall as a means to absorb shock loads. The end cap of this patent is also provided with at least one crush button for absorbing shocks applied along the longitudinal length of the fragile article.
Two related patents issued to DICKIE et al., U.S. Pat. No. 5,626,229 and No. 5,628,402 each are directed to a gas-containing product supporting structure which takes the form of a plastic bladder shaped on one side to provide a cavity having internal dimensions which match the external dimensions of the product to be protected, and shaped on its other side to have external dimensions which match the internal dimensions of the shipping container into which it is placed. The product is semi-rigid and self-supporting, monolithic, and gas-containing and may take the form of a corner piece or an end piece or tray for the product to be protected. The semi-rigid and self-supporting gas-containing bladder will retain its shape irrespective of whether it is sealed or open to the ambient surroundings; and will generally comprise a plurality of chambers in the interior of the product supporting structure with gas communication between the chambers so that the gas that is within the structure may flow from one chamber to another during shock loading circumstances of operation.
AZELTON et al. U.S. Pat. No. 5,799,796 teaches a unitary spring system end cap packaging unit. Here, the structure includes an inner wall, an outer wall, and a spring system disposed between them. The spring system includes at least one flexible harmonic bellows which forms a flexible ridge that has an arcuate shape along the length of the sidewall structure. A cushioning space exists between the edge of the inner sidewall and the edge of the outer sidewall. Dimples may be provided on the inner surfaces of the sidewall to allow a friction fit of the end cap to the product over which it will be placed. The arcuate harmonic bellows form flexible ridges that are elastic in nature; and each bellows of the spring system operates independently when a shock load is applied.
A co-pending United States patent application in the name of the inventor herein, Ser. No. 09/286,843, filed Apr. 6, 1999, teaches a cushioning device which has a molded post as an integral part thereof. The post is designed to extend into an intersecting corner between two perpendicular packaging container sides, or into the corner formed by three mutually perpendicular packaging container sides. A product supporting surface is spaced away from a related packaging container side by a container contacting flange and a curved ridge. In a shock loading situation, the curved ridge will at least temporarily be further curved away from the post, and the product supporting surface will at least temporarily move closer to it""s related packaging container side.
Two additional co-pending applications in the name of the present inventor are Canadian Patent Application Serial No. 2372480 which particularly teaches protective packaging enclosures which are formed as a clamshell, into which shock sensitive devices such as hard drives, CD and DVD drives, motherboards, etc., can be placed; and U.S. patent application Ser. No. 09/490,848 filed Jan. 24, 2000, which teaches unitary product cushioning structures which may have a variety of configurations such as caps, edge pieces, trays, and the like. The latter application provides shock absorption support for shock sensitive products in at least two of three mutually perpendicular directions, typically in all three, by the provision of an outer container contacting wall at each side which is intended to contact an outer packaging container.
The present inventor has unexpectedly discovered that an inexpensive moldable plastics material may be employed in the production of end caps in keeping with the present invention, where the end caps have a plurality of deflection elements which extend diagonally away from the corners of a product receiving cavity. Thus, contrary to some of the prior art discussed above, contact with an outer packaging container occurs only at the ends of the container, and in the corners of the container at the ends, rather than at the end walls and outer top and bottom and side walls of the outer packaging container.
Accordingly, the present invention provides a unitary protective packaging device for shock sensitive products which are shipped or stored in an outer packaging container, with the intention that a pair of such unitary protective packaging devices will be employed, one at each end of a shock sensitive product, and with the understanding that the outer packaging container is rectilinear in configuration.
The unitary packaging device comprises a product receiving cavity which is surrounded by product contacting walls, and where the product receiving cavity has a product supporting platform in the lower region thereof.
There is a base portion below the product receiving cavity, which has two pairs of deflection elements extending diagonally away from the corners of the product receiving cavity towards external outer packaging container contacting corners. Also, the base portion has bottom outer packaging container contacting lips at the bottom side thereof.
The distances between adjacent pairs of outer packaging container contacting corners are substantially equal to but not greater than the internal distances between adjacent pairs of corners of the inner packaging container with which the unitary protective packaging devices are to be employed.
The pairs of deflection elements are adapted to flex away one from another under shock loading conditions, and the bottom outer packaging container contacting lips are adapted to spread away one from another under shock loading conditions.
Accordingly, shock protection for a shock sensitive product in an outer packaging container, and having a unitary protective packaging device at each end thereof, is provided in three mutually perpendicular directions.
Typically, the configuration of the product receiving cavity of the unitary protective packaging device in keeping with the present invention, is rectilinear.
In some embodiments of the present invention, a U-shaped channel may be formed around the periphery of the product supporting platform.
Also, in some embodiments of the present invention, the product supporting platform may be formed having an upwardly curved configuration.
Typically, the product receiving cavity has a rectangular configuration, with one pair of opposed product contacting walls being longer than the other pair of product contacting walls.
Also, typically a downwardly directed notch may be formed in each of the longer product contacting walls.
In any event, a downwardly directed notch may be formed in at least one pair of opposed product contacting walls.
Each of the deflection elements is formed at least at the external outer packaging container contacting corners thereof so as to slope downwardly and outwardly towards the bottom outer packaging container contacting lips.
Also, the bottom outer packaging container contacting lips may be formed so as to extend outwardly from the base portion in the bottom region thereof.
When the product receiving cavity has a rectangular configuration, there may be an additional outwardly directed stiffening rib which is formed in the base portion between the external outer packaging container contacting corners on the sides of the base portion beneath the longer product contacting walls of the product receiving cavity.
Still further, an outwardly directed stiffening rib may be formed in the base portion between the external outer packaging container contacting corners in each of at least one pair of opposed sides of the base portion.